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1-Visitor
February 11, 2025
Solved

Plotting failed. replace complex values and NaNa by real number.

  • February 11, 2025
  • 2 replies
  • 978 views

SB_12880552_0-1739270230701.png

SB_12880552_1-1739270248066.png

SB_12880552_2-1739270261945.png

Mathcad prime 9.0

This is quite a lot to look at, but I'm struggling with getting this graph as well as the following two to accept my values. I'm relatively new to Mathcad, so any tips would be more than appreciated.

ive tried expanding my values to use less variables, but nothings seems to help this issue. 

Best answer by Werner_E

According your problem that some functions, which were  derived via symbolic evaluation, are considered "not defined" when later used numerically:
The cause is that with the symbolic evaluation the units loose their label "Unit" and are treated as unknown variables and so a later numeric evaluation fails.

To cope with this problem PTC has implemented the option "Units/Constants in Symbolics" in the Calculation Options.

You should turn on this option and then recalculate the worksheet.

Werner_E_0-1739277094391.png

Actually I don't understand why this option is not turned on per default.

 

Your unit problem is based an the fact, that your parameter t is used dimensionless and not as dimension time.

That way integration over t does not change the unit and your velocity and displacement are still of dimension acceleration.

You may correct this by multiplying the definition of v and S by seconds (see attached worksheet), but IMHO the better approach would be to use t as time throughout which also means that you would have to write something like sin(t/s) instead of sin(t) or sin (omega t) with omega as frequency.

Werner_E_0-1739283562481.png

 

 

2 replies

23-Emerald IV
February 11, 2025

Check your units. On the x-axis: RG.z(T) gives m/s, instead of inch so cannot be added to r.a * sin(...)

Success!
Luc

1-Visitor
February 11, 2025

thank you, that fixed my graphs... now i just need to fix my formulas.

 

 

Catalina
Community Moderator
February 18, 2025

Hi @SB_12880552,

I wanted to see if you got the help you needed.

If so, please mark the appropriate reply as the Accepted Solution or please feel free to detail in a reply what has helped you and mark it as the Accepted Solution. It will help other members who may have the same question.

Of course, if you have more to share on your issue, please pursue the conversation.

Thanks,

Catalina | PTC Community Moderator
Werner_E25-Diamond IAnswer
25-Diamond I
February 11, 2025

According your problem that some functions, which were  derived via symbolic evaluation, are considered "not defined" when later used numerically:
The cause is that with the symbolic evaluation the units loose their label "Unit" and are treated as unknown variables and so a later numeric evaluation fails.

To cope with this problem PTC has implemented the option "Units/Constants in Symbolics" in the Calculation Options.

You should turn on this option and then recalculate the worksheet.

Werner_E_0-1739277094391.png

Actually I don't understand why this option is not turned on per default.

 

Your unit problem is based an the fact, that your parameter t is used dimensionless and not as dimension time.

That way integration over t does not change the unit and your velocity and displacement are still of dimension acceleration.

You may correct this by multiplying the definition of v and S by seconds (see attached worksheet), but IMHO the better approach would be to use t as time throughout which also means that you would have to write something like sin(t/s) instead of sin(t) or sin (omega t) with omega as frequency.

Werner_E_0-1739283562481.png